ADVANTAGES OF ULTRAVIOLET IRRADIATION IN MODELING OXIDATIVE STRESS IN VIVO IN THE PROJECTION OF PHARMACOLOGICAL STUDIES

Abstract

Creating an in vivo model of oxidative stress is essential for establishing the antioxidant activity of registered medicines and/or for identifying new antioxidants, the range of indications for which is expanding annually. Preclinical studies on modeling oxidative stress by exposure to low and high temperatures and ultraviolet irradiation were conducted in 2020-2021 at the Central Research Laboratory of the Amur State Medical Academy (Blagoveshchensk, Amur Region, Russia). For the experiment, 80 male rats were divided into four equal groups. In the first group (intact), animals were not exposed to any effects, in the second group (experimental 1), animals were subjected to hypothermia (-15°C 180 min/day daily for 7, 14 days), in the third group (experimental 2), animals were exposed to hyperthermia (+40±2°C 45 min/day daily for 7, 14 days), in the fourth group (experimental 3), animals were exposed to ultraviolet irradiation (15 M/m² 3 min/day daily for 7, 14 days). The results of the experiment established that modeling of oxidative stress by ultraviolet irradiation leads to the accumulation of lipid peroxidation products by 46-63% (p < 0.05) on the seventh day of the experiment, which is superior to the hyperthermia model in diene conjugation of lipids (p = 0.001837) and malondialdehyde (p = 0.000319). Analysis of the activity of the antioxidant system components indicated the effectiveness of modeling by all the tested factors due to a statistically significant decrease in the level of ceruloplasmin in the intact group by 31-34% (p < 0.05) at the end of the first week of the experiment and by 33-35% (p < 0.05) by the end of the second week, vitamin E by 22-31% and 19-30%, respectively (p < 0.05). A conclusion was reached regarding a more pronounced accumulation of peroxidation products under the influence of ultraviolet radiation over seven days, confirming the advantages of this experimental model, which is capable of inducing oxidative stress more quickly. The confirmed prooxidant effect of ultraviolet irradiation in vivo is recommended as an experimental model for the development of oxidative stress over seven days for pharmacological studies related to the search for new antioxidants.